Process of producing castings having chilled and machinable surfaces in permanent molds.



E. A. OUSTEB.

PROCESS OF PRODUCING GASTINGS HAVING GHILLED AND MAGHINABLE SURFACES IN.

PERMANENT MOLDS.

APPLICATION FILED DEG. 12, 1910.

Patented Apr. 9, 1912.

IJI villilliili wi/tvwooeo aw EDGAR A. CUSTER, OF PHILADELPHIA,PENNSYLVANIA, ASSIGNOR TO THE SANDLESS CASTING COMPANY, OF PHILADELPHIA,PENNSYLVANIA, A. CORPORA- TION OF DELAWARE.

PROCESS OF PRODUCING CASTINGS HAVING CHILLED AND MACHINABLE SURFACES INPERMANENT MOLDS.

Specifieationof Letters Patent.

To all whom it may concern:

Be it known that I, EDGAR A. CUs'rER, a

citizen of the United States, residing at Philadelphia, in the State ofPennsylvania, have invented certain new and useful Improvements inProcesses of Producing Castings Having Chilled and Machinable Surfacesin Permanent-Molds, of which the following is a specification.

The primary object of this invention is to produce a casting in apermanent mold which will have chilled surfaces and which will also haveparts or surfaces of relatively soft and easily machinable metal.

A further object of the inventionis to produce such a casting which willbe free from strains or distortion of casting without a subsequentannealing or similar treatment.

The various other objects of the invention will be more fully set forthin the following description of my improved process, which consists inthe new and novel steps and combinations of' steps hereinafter set forthand claimed.

In the accompanying drawing is shown one form of apparatus adapted'forcarrying out my improved process, in which- Figure 1 is a side elevationpartly in section of a mold adapted for carrying out my process, showingthe casting in place therein. Fig. 2' represents an end view of themold.

The mold shown in the drawings is adapted for casting car wheels orsimilar articles, and comprises a plurality of parts which aremovableindependently of each other. The mold is mounted preferably upona suitable platform a having suitable levers pivoted thereto foractuating the parts of the mold.

The mold comprises two main sections, 0 and d respectively, one of whichcan'be drawn apart by the levers c to remove the casting b, and thesesections provide bearings for the other parts or sections of the mold. Amovable core 6 is mounted in the section 0 and is preferably tapered toform the axle bearing. Said core may be withdrawn by the lever e. Thesection 7, which may be withdrawn by the lever f operating through linksF, is mounted in the section 03 and is recessed to form the spokes. Thesectiondis suitably recessed to form the tread and may be provided withan insert d. The

section a is correspondingly recessed to form a portlon of the flange.These recesses in the several parts register to form the matrix PatentedApr. 9, 1912.

of the mold. The metal is supplied to the matrix through a suitable.sprue h preferably formed in the meeting faces of the sec-' tions 0 andd.

In practicing my improved process the heat is conducted away fromcertain portions of the casting such as the rim, much more rapidly thanfrom other portions of the casting by making the adjacent sections ofthe mold of large heat-absorbing capacity, so as to cause the metal toset more deeply and thus prevent the parts of the wheel from pullingapart. The molten metal which fills the matrix of the mold is broughtswiftly to the point of setting and the core 6 is withdrawn as soon asthe metal has set, so that it will be soft and easily machinable.Promptly thereafter the section f and the section 0 are withdrawn, thusfreeing both the hub and the spokes from contact with the mold. Thewheel, however, is left in position and in contact with the section dfor a suitable period of time after the metal has set, and may be leftuntil the tread and flange have become chilled. Thereupon the wheel isremoved and allowed to cool to normal atmospheric temperature.Consequentlyv the hub and spokes of the wheel will consist of relativelysoft and easily machinable homogeneous metal, but the tread and flangewill possess the desired hardness which results from chilling.

By means of this process I am enabled to produce castings havingsurfaces or parts of varying degrees of hardness, and at the same timeproduce a casting of homogeneous structure free from internal strains.If desired the rim and s okes may be made of harder metal than t e hubby allowing the same to remain in contact for a longer period of timewith the contiguous portions of the mold. Although the mold shown in thedrawings is adapted for casting a car wheel on edge, it is obvious thatthe same maybe cast in a horizontal position and that my improvedprocess is not limited to car wheels but may be used in the productionof castings of any shape or design in which it is desired to producesurfaces or parts of varying degrees of hardness. 1

I claim as my invention:

1. The process of producing castings having chilled and machinablesurfaces in permanent molds, which consists in removing the mold fromone portion of the casting as soon as the metal has set, causing anotherportion of the casting to set-more deeply than the first mentionedportion and permitting a part of said last mentioned portion of thecasting to remain in contact with the mold until it has chilled, andthen removing the casting from the mold and allowing it to cool.

2. The process of producing castings having chilled and machinablesurfaces in permanent molds, which consists in pouring the metal in apermanent mold comprising a plurality of parts, bringing said castingthroughout swiftly to the point of setting, vremoving a portion of themold out of contact with the casting as soon as the metal contiguous tosaid portion of the mold has set, conducting the heat more rapidly fromthe remaining portions of the casting, and causing a portion of thecasting to remain in contact withthe mold until the metal in saidportion of the casting has chilled.

, 3'. The process of producing castings comprising a hub and a treadportion in permanent molds, which consists in bringing the.

portion to remain in contact with the mold until the same has chilled,and. then removing said casting from the mold and permitting-the same tocool to normal'at-mospheric temperature.

4. The process of producing wheels having a chilled tread and amachinable hub in permanent molds, which consists in bringing the metalof the casting swiftly to the point of setting, then first removing themold out of contact with the hub portion, then secondly removing themold out of contact with the spokes and then thirdly removing the moldout of contact with the rim, and permitting the tread portion of thecasting to remain in contact with the mold until the same has chilled,and then removing said casting from the mold and permitting the same tocool to normal atmospheric temperature.

5. The process of producing casting comprising machinablesurfaces andrelay tively hard surfaces in apermanent moldi:

which consists in bringing the castin swiftly to the point ofsetting'and snnul taneously causinga portion of the castm to set moredeeply [than other portion thereof and then removing the casting from} 1the mold and allowing it to cool to normal A atmospheric temperature.

This specification, signed and wan this 1st day of December, A.D.,,11910.' "1

EDGAR A. CUSTER. 1

Signed in the presence of AMBROSE LJOSHEA, HELEN M. DAMES'.

